Advances in software and ineptitude at the studios in handling their property (amongst others in the situation described above in Foundation's case), have to this day caused CGI models to be of a far more fleeting nature than physical models. Lebowitz explains:
"When a CGI company is hired to do FX for a production, in theory all the assets they create are property of the studio. A smart studio should probably ask for regular backups of data for a variety of reasons, most important of which would be safety backups and potentially the need to re-create the work elsewhere. However, this rarely happens, most probably because it's just not anyone's assigned job. Who asks for the data? Who checks it? Where do they store it? Who keeps the records? All this would need to be answered and a process implemented and in most cases, either no one has thought it through or wanted to spearhead a new headache. Even if the data was backed up, if someone wanted to load up a spaceship model ten years later, success would be hard to come by. Do they have the right software? Since no two companies ever name their hard drives with the same letters or use the same directory structure, will the new user know where to find the files when their computer tells them, 'can't find G:/spaceship/wingtip/test/nogood/deleteme/finalimages/nosecone.png?' Even if all the ducks are in a row, often times the CG company, knowing full well the data they provide might be used to cut them out of the picture, will purposely not make it easy for the studio. Sure, they'll provide the models as asked, but not the setup/assembly files (hey, setup files are technically NOT the model). All this means is that the more time passes, the less likely it will be to re-create CG scenes. If all the data and the directory structure on a company's hard drive remains untouched, it's fine, but the moment you start to back stuff up and clear it off the server, your chances of success begin to dwindle.
